Best RPM to shift?
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From: Flying on the H1 w/ 75 psi of compression on all 4 cyl
Car Info: PnP VF30 w/ STi injectors Perrin intake walbro fuel pump w/ a TXS TBE
i shift about 7200 rpms in 1,2,3 then 4th at 6800 rpms but w/ a mostly stock rex there should be no need to go to 4.
have fun drive safe
mario
have fun drive safe
mario
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everyone always tells me shift as high as you can...BUT from a very reputable source i heard shift right at max hp which is like 6500....no higher...which i agree with personally. but wait for other opinions...but make sure they are real drivers...not kids that just think they are racers cause they do it on the weekends
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I've been drag racing my WRX at the California Speedway since September of 2001. Back then when my car was stock with just over 6000 miles on it, I've tried many different shift points and here's what worked for me:
1st to 2nd @ 7200 RPM
2nd to 3rd @ 6700 RPM
If you're running stock, just tach out in 3rd gear instead of trying to shift into 4th, unless you're good at speed shifting. You'll notice that you'll hit Redline as you near or cross the 1/4 mile mark. If you're running with mods, most likely you'll need to shift into 4th gear, then shift somewhere between 6500 and 6700 RPM, depending on boost levels.
Except for going from 1st to 2nd, I don't shift at or above Redline for the following reasons:
1) I've noticed that the horsepower drops off considerably after 6800 RPM
2) Torque also drops off to insignificant levels at over 6700 RPM
3) Effective boost levels begins to drop as early as 6500 RRM.
The reason why I shift at 7200 RPM when going from 1st to 2nd gear is because I want to be at the highest possible RPM with as much usable torque when entering 2nd gear. The problem with shifting at lower RPMs when going into 2nd gear is that there's not enough torque and the car doesn't pull as hard.
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2002 Subaru Impreza WRX
1/4 Mile: 13.83s @ 96.85MPH (as of January 2003)
http://members.cardomain.com/uncle_dan
Dan
1st to 2nd @ 7200 RPM
2nd to 3rd @ 6700 RPM
If you're running stock, just tach out in 3rd gear instead of trying to shift into 4th, unless you're good at speed shifting. You'll notice that you'll hit Redline as you near or cross the 1/4 mile mark. If you're running with mods, most likely you'll need to shift into 4th gear, then shift somewhere between 6500 and 6700 RPM, depending on boost levels.
Except for going from 1st to 2nd, I don't shift at or above Redline for the following reasons:
1) I've noticed that the horsepower drops off considerably after 6800 RPM
2) Torque also drops off to insignificant levels at over 6700 RPM
3) Effective boost levels begins to drop as early as 6500 RRM.
The reason why I shift at 7200 RPM when going from 1st to 2nd gear is because I want to be at the highest possible RPM with as much usable torque when entering 2nd gear. The problem with shifting at lower RPMs when going into 2nd gear is that there's not enough torque and the car doesn't pull as hard.
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2002 Subaru Impreza WRX
1/4 Mile: 13.83s @ 96.85MPH (as of January 2003)
http://members.cardomain.com/uncle_dan
Dan
Last edited by Uncle_Dan; May 28, 2003 at 11:33 PM.
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From: Flying on the H1 w/ 75 psi of compression on all 4 cyl
Car Info: PnP VF30 w/ STi injectors Perrin intake walbro fuel pump w/ a TXS TBE
hey there Uncle Dan i liked ur web site. it was interesting if u wouldn't mind could u send me some tips and pics on how u installed your dual staged boost controller.
thank you
mario
thank you
mario
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Tips on installing a MBC
Originally posted by mario
hey there Uncle Dan i liked ur web site. it was interesting if u wouldn't mind could u send me some tips and pics on how u installed your dual staged boost controller.
thank you
mario
hey there Uncle Dan i liked ur web site. it was interesting if u wouldn't mind could u send me some tips and pics on how u installed your dual staged boost controller.
thank you
mario
Thanks for visiting my website and I'm glad you liked it. In regards to your request for instructions, tips and pics on how I installed my TurboXS Dual Stage Manual Boost Controller, well...I'm sorry to say that I don't have any pics except for the ones I have on my website after it was installed. I can, however, try to give you some instructions and tips.
To start and for me to help you with tips, do you have any questions or concerns about anything specific regarding the installation you want to ask me?
If you want to create a new "Public" thread for this, then let me know and I can try to answer your questions there. There maybe others with hints and tips that could be helpful and useful for anyone who is installing a manual boost controller.
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2002 Subaru Impreza WRX
1/4 Mile: 13.83s @ 96.85MPH (as of January 2003)
http://members.cardomain.com/uncle_dan
Dan
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From: Huntington Beach, CA
Car Info: 03 Sonic Yellow WRX Sedan
well for my fastest run of 135 mph, i went past 7 up through 3rd and shifted at like 6500 in 4th - 5th gear, then the car began to pull again. but you will notice the rpms struggling to move up in 4th gear and the speed also struggling... by shifting into 5th you are put back in your powerband and it just climbs!
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From: Longing for my ol' white '02 WRX :(
Car Info: 2016 Acura RDX ... meh. Um, nice subwoofer?
Shifting at peak power is skydiving with huge helium balloons.
...think of a horsepower curve from a dyno chart for your car. OK, got the image in your head? Power bands in drag racing is all about continuously keeping the engine in a state where its getting the highest possible area under that curve.
Shifting early - you have too much low RPM power production. Less torque, less horsepower, less accelleration. You might as well be in an OZ Rally Lancer.
Shifting late - you have a very similar problem, but now you're also wasting engery via wasted RPMs and you take the chance of hitting fuel cut (for those w/o an a defenser).
So what's shifting just right? You want to make sure that your shifts containt as much as the top of your power band as possible... highest area under the curve. On my mildly modified WRX this means about what someone else said, "7200". And I've proven this. The difference between shifting at redline and 7200 got me almost 0.3 seconds consistently. You want to go THRU your peak.
Getting your car dyno'd is a great way to figure out exact shift points. Even better is to get datalogging to see how your RPMs drop from gear to gear depending on when you shift. Just from perfecting shift points you can gain from 1/4 to over 1 full second.
jason
...think of a horsepower curve from a dyno chart for your car. OK, got the image in your head? Power bands in drag racing is all about continuously keeping the engine in a state where its getting the highest possible area under that curve.
Shifting early - you have too much low RPM power production. Less torque, less horsepower, less accelleration. You might as well be in an OZ Rally Lancer.
Shifting late - you have a very similar problem, but now you're also wasting engery via wasted RPMs and you take the chance of hitting fuel cut (for those w/o an a defenser).
So what's shifting just right? You want to make sure that your shifts containt as much as the top of your power band as possible... highest area under the curve. On my mildly modified WRX this means about what someone else said, "7200". And I've proven this. The difference between shifting at redline and 7200 got me almost 0.3 seconds consistently. You want to go THRU your peak.
Getting your car dyno'd is a great way to figure out exact shift points. Even better is to get datalogging to see how your RPMs drop from gear to gear depending on when you shift. Just from perfecting shift points you can gain from 1/4 to over 1 full second.
jason
Last edited by mmboost; Jun 4, 2003 at 02:01 PM.
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